Obama declares emergency in rain-soaked South Carolina

Neighbors watch employees with the city of Isle of Palms cut down a live oak tree that fell down on 23rd Avenue after heavy rains fell on Sunday, Oct. 4, 2015. The South Carolina coast is getting hammered with heavy rains along with an unusual lunar high tide causing flooding all over the state.

As hurricane Joaquin is weakening and moving offshore over the Atlantic, it has left behind unprecedented rain and flash flooding, prompting President Barack Obama Saturday to declare an emergency in South Carolina and to promise federal aid.

CNN reports that three people died on Friday and Saturday in traffic accidents in South Carolina, and another person died in a car accident in North Carolina on Thursday when a tree fell on Interstate 95, as rushing water and wind surges of 30 miles per hour along the coastline whipped the state.

Emergency workers pulled people out of cars stuck in rushing flood waters last night, while the National Weather Service issued 42 weather warnings and advisories for the state, including warnings for flash floods in three counties.

"What we're experiencing is an unprecedented event," said Mayor Joseph Riley Jr. in a news conference Saturday, referring to the record rainfalls and extremely high tides happening at the same time, according to CNN.

State emergency agencies have been urging people to avoid going out on the roads, even if flooding in their areas doesn’t seem too deep.

Remain. Where. You. Are. Dangerous flooding conditions through the state for most of the day. #SCFlood#SCtweets

Hundreds of people were calling 18 agencies for help overnight, reported CNN. The state’s emergency management division said on Twitter last night that four additional swift-water teams were coming from out-of-state to help.

Charleston saw 11.5 inches of rain on Saturday, a record for the city says ABC News, and could see that much more before the storm moves out, potentially on Monday. Some people are using kayaks and paddleboards to get around.

The Christian Science Monitor reported on Saturday that the weather phenomenon causing the severe weather is called a “Rex block,” discovered by Dr. Daniel Rex in 1950. As hurricane Joaquin moves north it has caused low atmospheric pressure to mix with high pressure below it to form an unrelenting block of severe weather above South Carolina.

The weather is expected to hit other states, with a foot of rain possible in the Southern Appalachians, reports CNN, and two inches possible in the Northeast. Up to four inches could hit the waterfront between Georgia and New Jersey.

Besides the Carolinas, New Jersey and Virginia have declared states of emergency, as coastal and low-lying parts of the tristate area are very likely to see impacts, reported The Weather Channel.